Orifice meter



PATENT JOHN C. DIEHL, 01? ERDE, PENI\TSYLVANIA ASSIGNOR 'l@ AMERICAN METER COll/Z'PANY, OF NEW YQRIK, Il. Y. A GORPORA'IION OB DELAWARE OREFICE 1*EETER Application fi1e c cober 18, 1.928. Sezial l1o. 313,331.

@rifioe meners as ordinarily macle are providecl with meaus for measuring the (liflerential pressure as betweon tho pressurcs at the up-stream an l lownstream sides of the orifico. Thoso differential pressuro dovices commonly involvo Ehe use oft a U-tuhc, tl1e liquid being usually in oho form of morcury. lVith Sud(lon fluctuations of prcssura. the1e is a toncloncy to throw l'ho morcury out oi tho U-tuloo, not only involx'ing a loss of tho m01- cury hut also (l110 t.o fl1is loss, if not cliscovurod resulting in a faull y action of tl1o moter. 'lhere is oftvn lo1'oigli matter (raniml into ono leg of lho U-tuho this also rosulting in laulty action ol thc dovice. 'lll1is lil'iicull ha s heretofore hoen tal en (fl10 o1" h y supplying check valvos a'u auch side of tl1e U-tube preventing a flow irom tho U-tuloo to tho connect1ons loa lmg lo the condmi; llnasmuch as ifil1ese violent fiuctuations almost invarialoly arise in tho connoctio1flemling to tl1e up-stream si(l0 l havo found lhat by chocking an inflow from this up-stream conncc tion when thero is a violent vari'ation it is possihle to avoi l an injurious action upon the mercury, o1 liquid in tho U-tube. Features und dotails of my invontion will appear from the following specilication an claims.

preferre embodimont 013 the invention is illusratml in tho accompanying drawing showingr'a front view 01? tl1o (lillorential. foa tun: of an oriiice metor, partly in seotion.

1 marks the concluit, 2 an orifice in the couduit, ancl 3 a U-tube. Ono end of tho U-tuho terminates in a fioat chaxnber 4 an l the opposite end in a small chamher 5. The chamber 5 is connectod with tho condui'u at tho upstroa1n si le of. the orifioe by a 'pipe 6 ancl the chamber 4: is connecteclwith the concluit at the down-stream si le of the orifice by a pipe 7.

A float 8 operates in the chamber. lt is connected by an arm 9 with a shaft 9a on Which is arrange a peu arm 10 operating 011 a chart 11 the chart 11 being actuated from a mechanism carried in a case 12. The U-tube is supplied With a liquid, as before stated, usually merbury 13. These parts are of ordinary und well-known construction.

A check valve 14 is arranged in the counection 6 und. operates on a seat 15. When closed it prevents a movement of fiuid from the connection 6 to the chamber 5. This check valve isconnected by a stem 16 with a floaii; 17 this fioat being formed by an ordinary plante of melal lighter than nhe man cury and being cup shaped so filmt if tl1e mercury is forced below lt, il; Will. trap a quantity of morcury and thus increase its iveighiz. 'lhe float with the slom und valves is nicely adjusted as t0 wcight with relation o t-he part actecl upon by tho morcury that il l1olcls tho valve 14 normully in its open osition. A shouldor 18 limil;s the upwarcl movement of the valvo 14l-. This shouldor 18 may loe adjustecl toafford in itsolf a closuro of the connection to Ehe pipo 6, if desirocl, to provent an out-flow of mercury 011 a sudden roduction in prossure in (he up-stream side ol the. line. In such caso tho range 0f movemont lninging the shoulder 18 to closiug position or tl1e valve 14 to closing position shoul l he equal to the normal range of levels of tho mercury.

'hat l (llllll as new is:

l. ln a. lill'montial prossuro indicating device, the combination of a U-tube; a liquid in lhv Utulw: prvssmo pipos lo:uling to the. on ls ol' ihn U-tulw: a Check valvo at tho entranco to the U-rubo chocking an abnormal infiow to tl1c U-tubo: a float in tho U-tubo; moans connovling lho fioat to tho cho(k valve so thal: tl1v flonl1 will hohl tho. chock valvo normally opon an l Sill(l float being sublneiged und retarding tho clown-flow of liquicl abovo it.

2. lln an orifico 1n0t01, the combination oii a conduit; an orifice plate in tho conduit: a (lilloienial prossurv clovico comprising a U- tuhe: means connecting its en is Wlllll tlio couluit at tho opposito si(l0s of the orifice plate: a liquid in the U-tuhe: a chcvl VulVo, at lzho ontranco to the U-tube checking an abnormal inflow to the U-tube; a fioas in die U-tube; means connecting tho float to the check valve so thal; the float will hold the checlc valve um mally open sai(l float being submorgocl an l retardir xg th'e down-flow of liquid above it.

3. In a cliilorential pressure indicating cle vice, the combination of a U-tube; liquid in the U-tube; pressure pipes leading to the ends of tl1e U-tube; a check valve; a cup-shaped float in the U-tube adapted to hold a liquid when the liquid falls below the level of tho float; and means connecting the float to the check valve so that the float will hold the check valve normally open.

In testimony whereof I have hereunto sei:

my'hand.

JOHN C. DIEHL. 

